Additives for lubricating compositions



United States Patent 3,338,831 ADDITIVES FOR LUBRICATING COMPOSITIONS John Scotchtford Elliott, Eric Descamp Edwards, Gerald John Joseph Jayne, and Richard House, London, England, assignors to Castro] Limited, London, England, a British company v No Drawing. Filed July 8, 1965, Ser. No. 470,564 Claims priority, application Great Britain, July 9, 1964, 28,456/64 17 Claims. (Cl. 25232.7)

The invention relates to additives for lubricating compositions and also to lubricating compositions containing the additives. In particular, the additives with which this invention is concerned are detergents which are effective cold sludge dispersants.

In the lubricating of modern internal combustion engines deposits may be formed in the engines in two ways and there are two distinct problems involved in keeping the engines clean. One problem is the deposition of soot, lacquers and other deposits, mainly in the pistonring zone, under high speed, and consequently high temperature, operating conditions. These deposits may arise from partial combustion productsof the fuel or as the result of the oxidation or thermal degradation of the lubricant or both. This problem is alleviated by the addition to the lubricating oil of what are known in the art as high temperature detergents, conventional detergents or normal detergents. The other problem is the deposition of another kind of dirt. This dirt has become known as cold sludge. cold weather and under driving conditions obtaining in cities and in other conditions when the engines never truly warm up. This latter problem is alleviated by the addition to the lubricant of additives known as cold sludge dispersants. Cold sludge is derived almostentirely from the fuel andis normally wet.

In the past the conventional detergents have in general been metal containing derivatives Oforganic compounds such as basic alkaline earth metal petroleum or alkyl benzene sulphonates, basic alkaline earth metal salts of phosphosulphurised polybutenes or alkaline earth metal phenates. The cold sludge dispersants, on the other hand, have in general been copolymers of polar monomers such as N-vinyl pyrrolidone with oil solubilising copolymerisable monomers such as long-chain alkyl methacrylates.

More recently, products having useful detergent and cold sludge dispersant properties have been obtained by reacting a long chain monoalkenyl succinic anhydride, preferably polyisobutenyl succinic anhydride, with polyamines such as polyethylene polyamine or ,B-aminoethyl piperazine.

According to the present invention there is provided an additive for lubricating compositions which additive is a reaction product of (a) a long-chain monoalkenyl succinic anhydride, and (b) a reaction product of dicyandiamide with a primary alkylene polyamine having at least two primary amino groups and atleast one primary or secondary amino group from two to four carbon atoms removed from one of the primary amino groups. The novel additives of the present invention are high temperature detergents, and may also be cold sludge dispersants. It is preferred to use additives which have both properties.

The additive will generally have a nitrogen content Cold sludge is formed in engines in 3,338,831 Patented Aug. 29, 1967 sired degree of cold sludge dispersancy or detergency;

of the said reaction product.

The long chain-mono-alkenyl succinic anhydride may be obtained from the reaction between a normally liquid oil-soluble polyolefin having a molecular weight of from 700 to 3000, preferably from 750 to 1500, and maleic anhydride. Preferably the polyolefin is polyisobutylene.

The reaction may be carried out in a solvent such as toluene in the presence of a catalyst such as di-t-butyl peroxide, or in the absence of a solvent by heating the reactants at an elevated temperatur Reaction product (b) is prepared by reaction between dicyandiamide, otherwise known as cyanoguanidine, and a primary alkylene polyamine having at least two primary amino groups and at least one primary or secondary amino group not less than two carbon atoms and not more than four carbon atoms removed from one of the primary amino groups at a temperature of at least C. and preferably between 240 and 280 C.

The molar ratio of reaction product (a) to reaction product (b) may be varied from 1:1 to 5:1, preferably from 1:1 to 3:1, depending on the number of reactive nitrogen atoms in (b). In general 1:1 molar ratios are preferred, although when polyamines having molecular weights in excess of about 500 are employed it will be necessary to use a higher molar ratio of (a) to (b).

Preferably the alkylene polyamine has the general formula H H(RNH) -RNH2 where R is an alkylene radical, preferably CH CH and n is an integer from 1 to 5 or more.

Examples of suitable alkylene polyamines are diethylene triamine, triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine and mixed higher poly-' ing narrow ranges of molecular weights, those indicated being the most useful in this invention.

Another polyamine which is useful in this invention is one marketed by Union Carbide Limited under the name of Polyamine D dominantly a mixture of isomeric polyethylene hexamines of formula C H N and related hexamines containing piperazine rings and 12 C atoms. The average molecular weight of the mixture is approximately that of pentaethylene hexamine, i.e. 233, and the mixture contains a predominance of amines having 24 primary amino groups and at least two secondary amino groups.

The additives of this invention may be prepared by heating together the long chain alkenyl succinic anhydride (a) and the reaction product (b), at such a temperature as to remove the water of reaction and for sufiicient time to allow reaction to take place.

(PAD) which is stated to be pre The chemical nature of the reaction product (b) is not known with certainty and a mixture of products is normally formed. At 130 C. fairly rapid exothermic reaction takes place with evolution of ammonia. As heating is concontinued to 280 C. a further much slower reaction takes place with the further evolution of ammonia to yield a mixture believed to consist mainly of polyalkylenepolyamino-substituted melamines and/or polymers thereof. In preparing reaction product (b) molar ratios of dicyandiamide to polyalkylenepolyamine of from 6:5 to 3:5 may be used. Preferably a molar ratio of 1:1 is employed. When the molar ratio of polyalkylene polyamine to dicyandiamide exceeds 1:1 it may be necessary to strip off excess of polyalkylene polyamine under vacuum prior to reacting with reaction product (a).

For the purpose of calculating the amount of (b) to be reacted with (a), it was assumed that a single compound was formed from one mole of dicyandiamide and one mole of polyalkylene polyamine with elimination of one mole of ammonia, the approximate molecular weight of (b) being calculated on this basis.

The preparation of reaction product (b) is normally carried out by simply heating the two reactants together although solvents may be used, for example, water. However, when water is used as the solvent the resultant product is lower in nitrogen than when the reaction is carried out without a solvent, due to hydrolysis.

In the final reaction between the reactants (a) and (b), while it is believed that the main reaction product is a succinimide minor amount of secondary amides may be formed in addition to the imide. Furthermore, in cases where n in the polyalkylene polyamine is greater than 1, some reaction between (a) and the residual secondary amino groups in (b) may occur.

The lubricating compositions of this invention may exhibit adequate cold sludge dispersancy and high temperature detergency by the incorporation therein of quite small amounts of the additive, and the compositions may contain, for example, 0.1 to 10% by weight of the additive, and, preferably, from 0.5 to 5.0% on the weight of the composition. However, in some cases, particularly in the case when a lubricating oil concentrate is required, it may be desirable to use concentrations greater than 10%.

It is to be understood that the lubricating compositions of the present invention may contain also copper deactiva tors, pour-point depressants, antioxidants, viscosity index improvers and other conventional additives as necessary.

Particularly preferred antioxidants which may be used in conjunction with the additives of the present invention are the metal salts of dialkyl or di(alkaryl) or alkylalkaryl dithiophosphates, especially the zinc salts of dialkyl dithiophosphoric acids derived from C C alcohols. The dithiophosphate may be present in the composition in amounts from 0.2 to 2% and preferably from 0.5 to 1.5% by weight based on the weight of the composition.

Other additives which may be used with advantage in conjunction with the compounds of the present invention include alkaline earth metal salts of petroleum sulphonic acids, alkaline earth metal phenates or phenol sulphides, alkaline earth metal salts of phosphosulphurised hydrocarbons, any or all of which may be overbased and treated with carbon dioxide and dispersant viscosity index improvers such as copolymers of long chain alkyl methacrylates with heterocyclic nitrogen containing monomers e.g. N-vinyl pyridine or N-vinyl pyrrolidone.

There now follows by way of example a description of the preparation of a typical additive and of a lubricating oil composition according to the present invention.

EXAMPLE I Section A.-The preparation 0 polyisobutenyl succinic anhydride (1) 330 g. (0.3 mole) of a polyisobutylene of average molecular weight 1100, 32.34 g. (0.33 mole) of maleic anhydride and 3.82 g. (0.04 mole) of di-t-butyl peroxide were refluxed with stirring in 210 mls. of toluene, in a 2-litre flask fitted with thermometer pocket, nitrogen inlet, condenser and rotational stirrer, for 30 hours. The toluene was distilled OE and 210 mls. of hexane added, whereupon unreacted maleic anhydride was precipitated and this was removed by filtration using a filter aid. The hexane was distilled off and the product vacuum stripped for 1 hour at 200 C. and 10 mm. Hg pressure. The product was again filtered through a steam-heated filter funnel to yield 296 g. of a clear brown product. The purity of the product was determined by saponification. The saponification value was 73.5 mg. KOH/g. (calculated=93.5). The product therefore contained about 79% of polyisobutenyl succinic anhydride together with 21% of unreacted hydrocarbon.

(2) A similar product was obtained by stirring 1395 gm. (1.33 mole) of polyisobutylene of average molecular weight 1050 with 143.7 gm. (1.463 mole) of refluxing maleic anhydride and, when the reflux level dropped, heating to a temperature of 240260 C. for a further 20 hours. The reactants were allowed to cool, 1 litre of hexane added and the solution filtered through a diatomaceous filter aid. The hexane was distilled off and the product vacuum stripped for 2 hours at 200 C. and 10 mm. Hg pressure. 1397 gm. of a clear viscous liquid was obtained.

Saponification value of product=77.5

This product therefor contained 79.5% of polyisobutenyl succinic anhydride.

Section B.The reaction between tetraethylene pentamine and dicyandiamide 189 gm. (1 mole) of tetraethylene pentamine and 84 gm. (1 mole) of dicyandiamide were stirred together in a 500 ml. flask heated by a mantle and fitted with a mechanical stirrer, reflux water condenser and a nitrogen bleed. The temperature was slowly raised to C. during half an hour, when the dicyandiamide slowly dissolved and ammonia was evolved vigorously. The temperature of the orange-yellow slurry was then raised to 240-260 C. and kept there for 9 /2 hours. The product was a clear brown liquid at this temperature, but set to a brittle brown solid on cooling.

Percent N=42.8.

Section C.Preparation of a typical additive 0) the present invention 9.35 gm. of the product of Section B were stirred with 144.0 gm. of the product of Section A (2) in a beaker heated in an oil bath at 20 C. and blown with a slow nitrogen stream. After 8 hours, 153 gm. of Mineral Oil A were stirred in, a clear 50% solution of the additive in mineral oil thus being obtained.

Percent N=l.30 (calculated 1.29%)

Further examples of additives according to the present invention were prepared in a substantially similar manner to that in Example I, and the essential features of the reactions are presented in Table I. The polyisobutenyl succinic anhydride intermediates were all prepared as in Example I A(2), although in some cases it was not considered necessary to treat with hexane. The reaction products (b) were all prepared by heating the amine with dicyandiamide at 280 C. for 8 hours except where otherwise indicated. [he additives of the present invention were prepared by heating the polyisobutenyl succinic anhydride and reaction product (b) at 200 C. for about 8 hours after which time the additional mineral oil, which was a spindle oil having a viscosity of about 52 seconds Redwood I at 140 C., was added and the 50% concentrate then filtered.

A series of tests was carried out to illustrate the cold sludge dispersant properties in lubricants of the additives of the present invention. A simple laboratory test, designed to obtain information regarding the cold sludge dispersant properties of lubricants and additives, was

' performed in the following manner:

A quantity of cold sludge was collected from a Lauson engine which had been run deliberately under low temperature conditions using a leaded petrol and, as the lubricant, a plain mineral oil free from additives. This sludge was an emulsion containing from about to about 50% of water, the remainder containing from 0.8- 4.0% of lead, from 3-10% of material insoluble in pentane and from 140% of material insoluble in benzene, all percentages being by weight. The sludge (1 gram) was shaken for 30 minutes with 20 ml-s. of a light spindle oil having dissolved therein the additive under test on an automatic shaking machine and then poured into a measuring cylinder with a tapered base which was allowed to stand in an oven at 60 C.

- The cylinder was removed from the oven periodically and examined for signs of separation of the sludge. Changes in the colour of the oil proved to be the most reliable indication of sludge separation, the colour changing from black, blue or grey (depending on the sample of sludge used) through brown and speckled (in that order) to that of the clear oil. When the sludge was completely dispersed, the oil was black, blue or grey.

5% solutions of the 50% additive concentrates of Examples 1-4, 9, 12, and -18 in light spindle oil were prepared and tested in the above manner and were found to be comparable with prior art cold sludge dispersants in that the solutions were still black or grey after 4 weeks and in most cases up to 7 or 8 weeks.

In order to obtain some information on the dispersancy of the additives of the present invention at relatively high temperatures, such as those encountered in the piston ring-belt area of diesel engines, lubricating compositions containing them were subjected to Panel Coker Tests.

In this test the oil sample (250 ml. approx.) was contained in a sump which was fed by a chicken feed to maintain a constant level of oil. The oil was splashed continuously for 24 hours by means of Wires on a rotating spindle on to a heated sloping aluminium panel maintained at 275 C.

The weight change and appearance of the panels were observed after test, the appearance of the panels being assigned merit ratings according to a scheme in which A+ represented a perfectly clean panel, whilst D- represented a heavily lacquered and/ or sooted panel, anythingbetter than C+ being considered satisfactory. The base oil used throughout the test was a solvent refined mineral oil having a viscosity of about 160 seconds Redwood I at 140 F. The results of these tests are given in TableII. The tests showed that the additives of the present invention were effective dispersants under high temperature conditions and gave results somewhat better than the basic barium petroleum sulphonate which was a widely used metallic detergent. It has been found by experience that this test gives results which correlate well with tests in the Petter AV-l engine when this engine is operated under standard AT-4 conditions.

Typical lubricating oil blends of the present invention are given in the following examples, all percentages being by weight on the weight of the total composition.

EXAMPLE 34 Percent Mineral oil A 97.3 Additive of Example 2 2.0 ZDDP 1 0.7

EXAMPLE 35 Mineral oil A 97.3 Additive of Example 1 2.0 ZDDP 1 0.7

EXAMPLE 36 Mineral oil B 58 Mineral oil C 29 Additive of Example 2 4 ZDDP 2 1 VI Improver 8 EXAMPLE 37 Mineral oil blend D 91.3 Additive of Example 2 1.0 ZDDP 1 0.7 Additive A 2.0 VI Improver 5.0

EXAMPLE 38 7 Mineral oil blend D 91.3 Additive of Example 2 1.0 ZDDP 2 0.7 Additive A 2.0 VI Improver 5.0

EXAMPLE 39 Mineral oil blend D 89.6 Additive of Example 2 1.5 ZDDP .2 0.9 Additive A 3.0 VI Improver 5.0

EXAMPLE 40- Mineral oil B 56.9 Mineral oil C 28.6 Additive of Example 2 1.9 ZDDP 2 0.9 Additive A 3.7 VI Improver 8.0

Mineral oil A was a solvent refined mineral oil having a viscosity of about 160 seconds Redwood I at 140 F.

Mineral oil B was a mineral oil having a viscosity of about seconds Redwood I at F.

Mineral oil C-was a spindle oil having a viscosity of about 52 seconds Redwood I at 140 F.

Mineral oil blend D was a blend consisting of 87.5%

of mineral oil B and 12.5% of a solvent refined mineraloil having a viscosity of about 65 seconds Redwood I at 140 F.

ZDDP 1 was a mineral oil concentrate of mixed zinc dialkyl dithiophosphates derived from isopropanol and methyl isobutyl carbinol whilst ZDDP 2 was an essentially similar zinc dithiophophate derived from isopropanol and capryl (l-methyl heptyl) alcohol. The concentrates contained about 8.0% of phosphorus. Additive A was the barium salt of a phosphosulphurized polyisobutylene of molecular weight about 1000, the neutralization having been effected in the presence of an alkyl phenol, followed by treatment with carbon dioxide.

The V1. Improver employed was a copolymer of longchain alkyl methacrylates with n-butyl methacrylate, used as a 14% concentrate in mineral oil.

Examples 34 and 35 were suitable for use as I.C. engine oils and conformed to the Society of Automotive Engineers (SAE) 30 classification.

Examples 37, 38 and 39 were multigrade oils of the SAE 20W/ 30 type, Examples 37 and 38 being designed to have a performance level equivalent to that required by US Specification MIL-L-2104A and British Ministry of Defense Specification DEF 2101B, whilst Example 39 was designed to have a performance equivalent to that required by MIL-L-2l04A Supplement 1.

Examples 36 and 40 were multigrade oils of the SAE 10W/30 type, the latter being designed to have a performance level equivalent to that required by MIL-L- 2104A Supplement 1.

7 EXAMPLE 41 Percent Di(2 ethyl)hexyl sebacate 95.49 Product of Example 1 2.0 Phenyl-a-naphthylamine 1.0 3,7-dioctyl phenothiazine 1.5 Benzotriazole 0.01

In order to evaluate the high temperature oxidation stability of lubricating oils containing additives in accordance with the present invention, tests were carried out in Petter (registered Trademark) W-l engines operating under the following conditions:

Test duration 36 hours. Speed 1500:15 r.p.m. B.H.P About 3.3. Sump temperature 280 F. Coolant outlet temperature 302i2 F. Coolant inlet temperature 299 '-2 F. Fuel PE/IP reference gasoline.

The conditions for the Petter W-1 Test are set forth in the Institute of Petroleum Test IP 176/ 60T In this test the maximum rating for each of the components A, B and C was 10.0, the ratings therefore being merit ratings and not demerit ratings as in the AV-1 test. The general cleanliness of the piston, indicated in the composite rating A-I-B-l-C, together with the degree of oxidation of the oil, as adjudged by the corrosion, if any, of the copper-lead bearings, gave a measure of the oxidation resistance of the oil.

The results of these tests are given in Table III.

It will be seen from these tables that oil compositions in accordance with the present invention gave results of the same general order as the two conventional blends containing metallic detergents.

In order to evaluate the detergent properties of typical additives in accordance with the present invention at high temperatures, tests were carried out in a Petter (registered Trademark) AV1 engine, operating under the following conditions (AT-4 conditions):

Test duration hours- 120 Speed r.p m 1500 B.H.P. 5.0 Engine cooled with kerosine:

Sump temperature F 131 :4 Coolant outlet temperature F 185 Coolant inlet temperature F 173+3 Fuel sulphur percent .4

The AT-4 conditions are specified in the Institute of Petroleum Standards for Petroleum and its Products: Method IP 175/ 601". The results of these tests are summarized in Table IV.

These tests, in which the composite demerit rating A-l-B-l-C Was the most important criterion, showed clearly that the high temperature dispersancy of Examples 34 and 35 was comparable to that of a typical prior art composition containing a commercially available metallic detergent (additive A). The test on Example 36 showed how, by using a relatively high proportion of a typical additive of the present invention, the derating effect of the relatively large amount of V1. Improver present could be largely offset. Examples 38, 39 and 40 were typical multigrade oils and the tests on them demonstrated that a typical additive of the present invention would co-operate satisfactorily with a typical metallic detergent.

In order to obtain further confirmation of the cold sludge dispersant properties of additives in accordance with the present invention tests were carried out using a standard H 2 type Lauson engine, fitted with a false sump of about 600 gm. capacity, operating under the following conditions:

Part A Part B Part C Speed, r.p.m 1,840 1, 840 1, 840 Water outlet, F 210 210 Ftggl flow, time (seconds) per 605:1 60:;1 60:1

0.0. Ignition timing, degrees be- 25 25 25 low top dead centre.

According to blowby Nil 240 240 Uncontrolled-" 240 240 2nd hour Rising to 210 240 240 3rd-5th hours 210 240 240 6th hour Falling to own 240 240 level (no heat- Duration hours 3 x 6 12 2 The total duration of the test, after a preliminary /2 hour run in period without ventilation or sump heating, was 32 hours, Part A being run in three cycles, followed by Parts B and C. During Parts A and B, instead of normal crankcase ventilation, exhaust gas was fed in from a by pass into the crankcase breather at a slight pressure. The degree of ventilation necessary to produce a standard amount of blowby was determined during the run-in period by taking blowby readings at one minute intervals using a large gasmeter. The blowby was checked every 6 hours during the test and any necessary adjustments made.

- Under these test conditions substantial quantities of cold sludge were produced, the cleanliness of the engine being assessed on the basis of the weight of sludge on the tappet cover, on an adjacent baffie plate and in the sump. Additionally merit ratings were assigned to the front cover and to the engine as a whole.

The results of these tests are summarized in Table V, five lubricating oil compositions in accordance with the present invention being compared directly with a plain mineral oil and with two prior art compositions.

Compositions P and Q were both SAE 20W/ 30 oils having similar physical properties to Examples 37, 38 and 39 and have the following compositions:

Ccmposition: Percent Mineral oil blend D 90.4 Basic barium petroleum sulphonate (approx. 40% oil concentrate) 3.7 ZDDP-2 0.9 VI Improver 5.0 Composition Q:

Mineral oil blend D 92.3 Additive A 2.0 ZDDP-l 0.7 VI Improver 4.0 Dispersant VI Improver 1.0

The dispersant V.I. Improver was a commercially available o-il concentrate of a copolymer derived from long chain fumarates, vinyl acetate and N-vinyl pyrrolidone.

It will be seen that the lubricating oils of the present invention were markedly superior to the plain mineral oil and to the prior art compositions particularly in respect to overall engine cleanliness and the weight of sludge in the sump.

It will be appreciated from the foregoing test results that additives of the present invention in addition to being ashless and having good dispersant properties at high temperatures equivalent to those of commercially available metallic detergents may also have good cold sludge dispersing properties. The additives of the present invention may have significantly improved corrosion inhibiting properties compared to other succinimide derivatives of the prior art.

TABLE I Reaction Product (a) Preparation of Reaction Product (1)) Preparation ofAI(I11ditiVeS According to the vention Molecular Percentage Wt. of Percent Mole Addi- Percent Ex. weight of of PIB Wt. of dicyandi- Nitrogen Weight Weight ratio tional Nitrogen No. polyisosuccinic an- Amine amine amide in of (a) of (b) of (a) Mineral in butylenc hydride in (gm) (gun) product (gm.) (gm.) to (b) oil (gm) product product (inc. oil) 1, 050 85 730 l 420 40. 5 2, 026 319. 5 1:1 1, 146 2. 67 2 1, 050 84. 5 730 1 420 410 42. 6 1. 5 1 453 1. 78 3 1, 050 84. 5 292 168 40. 5 544 42. 6 2:1 583 1. 36 4 1, 050 84. 5 146 84 38. 413 27. 6 2. 1 441 1. 31 5 710 84 146 84 289 5 63 1 :1 354 3. 80 6 950 65. 5 292 168 40. 5 160 21. 3 1:1 180 2. 59 7 1, 400 78 292 168 4 42. 6 1 :1 427 2. 00 8 1, 900 61. 5 146 84 41. 7 162. 5 10. 65 1:1 172 1. 35 9 710 84 146 84 38.0 322 27. 6 2. 5 1 350 1. 66 10 1, 400 93 146 84 38. 0 533 27. 6 2. 5 1 561 0.93 11 1,050 75 52 42 44. 1 39. 2 3. 4 1:1 Nil 3. 62 12 1,400 78 o 103 2 84 44. 192 17 1:1 207 1. 98 13 1, 050 85. 1 Tetraethylenepentalmne 189 3 84 42. 8 360 23. 4 3:1 383 1. 37 14 1, 400 78 .do 189 84 36. 5 151 20. 1 1:1 216 1. 86 15 1, 050 84. 5 Pentaethylenehexamine. 232 84 36. 3 68. 5 3. 6 4:1 72 0. 96 16 1, 050 67. 5 Iminobispropylamine. 43 27. 6 38. 9 85 9. 9 1 :1 94 1. 69 17 1, 050 67. 5 Triethylenetetrarnine. 145 101 38. 0 170 23. 0 1:1 191 2. 60 18 1 Reaction time at 280 C. was only four hours.

2 Reaction time at 280 C. was only minutes.

3 The amine and dicyandiamide were refluxed for 12 hours in 200 ml of water followed by hearing for 5 hours at 280 C.

In the preparation of reaction product (b) the mole ratio of amine to dlcyandiamide was 1:1 except in the case of Example 18 where the ratio was 6: 5.

TABLE II.RESULTS OF PANEL COKER TESTS Example Additive 01' Percent ZDDP Weight Appear- No. Example N0. (wt.) in (Percent Increase ance blend by wt.) (mg.)

Base oil 165 D- Basic barium 3.7 0.9 2) 64.7 0- The numbers (I) or (2) 1n the ZDDP column are to gg f identify the actual zinc dithiophosphate antioxidant used f-g g-g i.e. ZDDP-1 or ZDDP-2. 2:0 0:9 (1 :1 11- The additive of Example 16A was prepared in the same 28 8:3 5 i: manner as that of Example 16 except that reaction prod- 6.0 0.9 (1) 27.4 5+ ucts (a) and (b) were reacted in 1:1 molar ratio instead 23 3;; g; 5 45 of 4:1. The product contained 2.36% N. 2.0 0.9 (2) 64.2 B 1.0 0.7 (1) 44.2 B 2.0 0.9 (1) 27.7 B 2.0 0.7(1) 62.0 B s 11 a 212 11 2. 2.0 0.9 (2 60.2 B

TABLE III.RESULTS OF PETTER W-l ENGINE TESTS A B 0 Blend A-l-B +C Bearing loss Skirt Land Groove (mg.) Rating Rating Rating Mineral oil A 6. 6 1. 3 1. 4 9. 3 1, 022 Mineral oil A with 0.7% ZDDP 6.8 1. 0 1. 0 8.8 5 neral 011 i gigg ing- 8.6 2.9 4. 7 16. 2 c

nera 01 W1 1 il l Pj g g% lg% a 10.0 8.4 3.9 27.3 5

1119!?! 01 17171 15% AdditiveA" 9.7 8.5 7.6 25.8 8 Example 34 X* 9.9 9.0 9.0 27.9 11 Example 35- 10. 0 9. 3 9. 0 28.3 12 Example 36- 9.8 7. 5 12 Example 38. 9.9+ 6.8 8 3 25.0 10 Example 39- 10.0 9.2 9 6 28.7 s

* This blend was identical to that 01 Example 34 except that 0.9% of ZD DP-2 was used in place of 0.7% ZDDP-1.

TABLE IV.-RESULTS OF PETTER AV-l ENGINE TESTS A B C Blend Average Average Skirt A+B+C Under Side Ring Groove Lan Lacquer Lacquer Lacquer} Lacqner/ Carbon Carbon Mineral oil A with 1.6% Additive A 75% ZDDP 1 3.8 5. 7 0.59 10. 1 1. 6 (Duplicate tcsts) 4.7 3.6 0.13 8.4 1.0 Example 34 4. 7 4.8 0. 22 9. 7 3. 3 Example 35... 5. 7 6.1 0.2 11.0 2. 5 Example 36*" 5.9 5.1 0.2 11.2 3. 3 Example 38. 6.4 6.4 0.6 13.4 3. 5 Example 39* 4. 0 5. 6 0.4 10.0 3. 3 Example 40*..- 4.1 6.7 0. 65 11. 4 2. 5

it 1 sulphur fuel was used in the engine tests reported in Table IV 36 39 and 40.

emerit l0=dirty.

for the oils of Examples TABLE V.-LAUSON ENGINE TEST RESULTS Weight of Sludge (grams) Merit Ratings Weight Blend l of oil in Tappet Bafiie Sump Front Overall sump (g.)

Cover Cover Mineral oil A 1.03 0. 51 17 7. 2 6. 5 450 1. 0.53 18 6. 6 6.3 412 Composition P 0.32 0.23 13 9.5 7. 8 387 1.16 0.65 24 9.1 5.9 510 Composition Q, 2. 33 1. 41 32 6.2 4.1 436 Example 34 1.17 0.33 9 9. 6 8. 7 357 1.00 0.32 7 9. 6 8. 7 406 Example 36 0. 47 0. 14 5 9. 7 9. 3 290 Example 37X... 1. 68 0.55 8. 7 7.8 397 0.84 0.40 10 9.2 8. 7 444 Example 39 0.33 0.20 6 9. 7 9. 2 332 0.24 0.11 3 9.7 9. 4 330 Example 40 0. 77 0. 51 12 9. 3 8. 5 495 Example 37X was Example 37, in which We claim:

1. A lubricating composition comprising a major proportion of a lubricating oil and from 0.1% to 10% by weight of a second reaction product of (a) a long chain mono-alkenyl substituted succinic acid or anhydride, said long chain mono-alkenyl substituent having a molecular weight of at least 700, with (b) a first reaction product of dicyandiamide with a primary alkylene polyamine having at least two primary amino groups and at least one primary or secondary amino group from two to four carbon atoms removed from one of the primary amino groups, said first reaction product being prepared by heating said dicyandiamide with said polyamine at a temperature of from about 130 C. to 280 C. and said second reaction product being a condensation reaction product.

2. A lubricating composition as claimed in claim 1 wherein the primary alkylene polyamine has at least one primary or secondary amino group two carbon atoms removed from one of the primary amino groups.

3. A lubricating composition as claimed in claim 1 wherein the primary alkylene polyamine has the formula H N-(RNH), -RNH where R is an alkylene radical having from 2 to 4 carbon atoms and n is an integer of from 1 to 5.

4. An additive as claimed ethylene and n is from 2 to 4.

5. A lubricating composition as claimed in claim 1 wherein the reaction product (b) is obtained from a reaction mixture containing a molar ratio of dicyandiamide to primary alkylene polyamine of from 6:5 to 3:5.

6. A lubricating composition as claimed in claim 1 wherein the reaction product (b) is obtained by heating the reactants together at a temperature of from 240 C. to 280 C.

7. A lubricating composition as claimed in claim 1 wherein the reactant (a) is obtained from the reaction between a normally liquid oil-soluble polyolefin having a molecular weight of from 700 to 3000 with maleic anhy- .dride.

in claim 3 wherein R is the additive of Example 2 was replaced by the additive of Example 1.

8. A lubricating composition as claimed in claim 7 wherein the polyolefin has a molecular weight of from 750 to 1500.

9. A lubricating composition as claimed in claim 7 wherein the polyolefin is polyisobutylene.

10. A lubricating composition as claimed in claim 1 wherein the additive is formed by heating reactant (a) and (b) in a molar ratio of from about 1:1 to 5:1.

11'. A lubricating composition as claimed in claim 10 wherein the molar ratio of reactant (a) to reactant (b) is about 1:1.

12. A lubricating composition as claimed in claim 1 containing from 0.5% to 5.0% by weight of the additive.

13. A lubricating composition as claimed in claim 1 containing from 0.2% to 2.0% by weight of a metal salt of a dialkyl or a di-(alkaryl) or an alkyl-aryl dithiophosphate.

14. A lubricating composition as claimed in claim 13 wherein the metal salt is a zinc dialkyl dithiophosphate, the alkyl group having from 3 to 10 carbon atoms.

15. A lubricating composition as claimed in claim 13 wherein the dithiophosphate is present in an amount of from 0.5% to 1.5% by weight.

16. A lubricating composition as claimed in claim 1 containing also as a viscosity index improver a copolymer of a long chain alkyl methacrylate with a heterocyclic nitrogen-containing monomer.

17. A lubricating composition comprising a major proportion of a mineral oil of lubricating viscosity, from 0.2% to 2.0% by weight of a zinc dialkyl dithiophosphate, the alkyl groups containing from 3 to 10 carbon atoms, and from 0.5 to 5.0% by weight of the condensation reaction product of (a) a polyisobutylene substituted succinic acid or anhydride wherein the polyisobntylene substituent has a molecular weight of from 750 to 1500, with (b) the reaction product prepared by reacting, at a temperature of from about C. to 280 C., di-

H N-( CH .CH .NH CH .CH .NH where n is an integer of from 1 to 5,

5 the condensation reaction product having been obtained by reacting the reactants (a) and (b) together in a molar ratio of from 1:1 to 5:1.

1 4 References Cited UNITED STATES PATENTS 3,219,666 11/1965 Norman et a1. 25251.5 X

DANIEL E. WYMAN, Primary Examiner.

P. P. GARVIN, Assistant Examiner. 

1. A LUBRICATING COMPOSITION COMPRISING A MAJOR PROPORTION OF A LUBRICATING OIL AND FROM 0.1% TO 10% BY WEIGHT OF A SECOND REACTION PRODUCT OF (A) A LONG CHAIN MONO-ALKENYL SUBSTITUTED SUCCINIC ACID OR ANHYDRIDE, SAID LONG CHAIN MONO-ALKENYL SUBSTITUENT HAVING A MOLECULAR WEIGHT OF AT LEAST 700, WITH (B) A FIRST REACTION PRODUCT OF DICYANDIAMIDE WITH A PRIMARY ALKYLENE POLYAMINE HAVING AT LEAST TWO PRIMARY AMINO GROUPS AND AT LEAST ONE PRIMARY OR SECONDARY AMINO GROUP FROM TWO TO FOUR CARBON ATOMS REMOVED FROM ONE OF THE PRIMARY AMINO GROUPS, SAID FIRST REACTION PRODUCT BEING PREPARED BY HEATING SAID DICYANDIAMIDE WITH SAID POLYAMINE AT A TEMPERATURE OF FROM ABOUT 130*C. TO 280*C. AND SAID SECOND REACTION PRODUCT BEING A CONDENSATION REACTION PRODUCT.
 13. A LUBRICATING COMPOSITION AS CLAIMED IN CLAIM 1 CONTAINING FROM 0.2% TO 2.0% BY WEIGHT OF A METAL SALT OF A DIALKYL OR A DI-(ALKARYL) OR AN ALKYL-ARYL DITHIOPHOSPHATE. 